Novo's Tresiba scores data for a new edge in insulin fight against Sanofi

One of Novo Nordisk's ($NVO) selling points for its new basal insulin Tresiba is safety. The drug triggers fewer episodes of hypoglycemia, a much-feared side effect of diabetes treatment, compared with other meds. But when the FDA finally approved Tresiba last fall, it didn't put that safety edge on the drug's official label.

Some new data could change that. Tresiba hit its primary goal in the SWITCH study, by cutting the number of hypoglycemic events by 30% compared with its head-to-head rival, Sanofi's ($SNY) Lantus. The rate of hypoglycemia on the Novo drug totted up to 186 events per 100 patient years, compared with 265 on Lantus.

As for hypoglycemia episodes at night--the drug's secondary goal--Tresiba cut those events by 42%. There were 55 events per 100 patient-years for Tresiba compared with 94 for Lantus.

That's a statistically significant difference, as Bernstein analyst Ronny Gal pointed out in an investor note when the study was released late last week. But is it significant enough to make a significant difference for the brand? That's the question.

As Gal pointed out, Tresiba delivered mixed results in severe hypoglycemia, missing on the "proportion of patients" who saw that problem, while hitting statistical significance on the "rate" of severe hypoglycemia. The actual, absolute numbers of severe events weren't published.

"The trial confirms (more thoroughly) the previous observation that Tresiba is better than Lantus on hypoglycemia," Gal writes. "The question is the clinical relevance of the difference. … Thus, the results are positive, but how positive is yet to be ascertained, in our mind."

Still, cutting the number of hypoglycemia events could be enough to help drive Tresiba sales, Gal figures. Particularly now, when it's just a head-to-head brand contest. The argument could be tougher after Eli Lilly ($LLY) and Boehringer Ingelheim's Lantus copy hits the market in December, but could be made nevertheless.

What's most likely to happen at that point, if Tresiba can establish a safety edge over Lantus, is that Novo would take share from the Sanofi med, rather than fending off biosimilars in a big way. After Lilly and Boehringer's Basaglar launches, Bernstein has estimated that the copies will grab 40% of the long-acting insulin market, with Sanofi's Lantus and newer Toujeo keeping about 30%, and Novo's Tresiba and Levemir, an older product, sharing the remaining 30%.

"Novo could now edge Sanofi in the long-run," Gal says. "[H]owever, there is still lots of uncertainty around Sanofi's approach." The firm is keeping its $1.7 billion forecast for Tresiba's 2020 sales in the face of the new data, at least for now.

- see the SWITCH release

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